the affair is corruption; inwardly it is rectification.
This digesting faculty continually transfers it from form to form, while the retaining faculty preserves its remaining there until the former governs it according to what its knowledge and its assigned task yield.
When the two have completed their work upon it according to that place, they leave it, and the attracting and expelling faculties take it. When these settle and transfer it to the other place, they return it to the retaining and digesting faculties. These do to it as they did in the preceding place, opening differing forms within it. The attracting and expelling faculties take it, conveying these forms along determined paths they do not exceed, as long as God wills to maintain this natural constitution. Without these agents, the vegetative soul could not attain its object.
(The Faculties' Weakness and the Constitution's Dissolution)
When God wills this natural constitution's destruction, the vegetative soul seeks appetite's assistance so that the governing soul may be moved to bring what it craves, but it does not do so. God weakens it through heat's sovereignty prevailing over its locus. It becomes weak as a lamp weakens within sunlight, remaining without a ruling.
The vegetative soul remains in its reality, saying to its agents, ‘I must have something through which to be nourished.’ It feeds upon the body's humors and the residues remaining within it. Its agents have also weakened like it. The constitution never ceases in increasing diminution, while the expelling faculty
